Phonomotor treatment and semantic feature analysis are two approaches to address anomia in individuals with aphasia. This study compares the efficacy of both methods in enhancing word retrieval and generalization to untrained nouns. The research involved 58 participants with chronic aphasia, focusing on their ability to name trained and untrained words. Significant improvements were observed in both treatment groups, but no substantial differences were found between them. This analysis is crucial for speech-language pathologists seeking effective strategies for aphasia rehabilitation.

Key Points

  • Compares phonomotor treatment and semantic feature analysis for aphasia.
  • Involves 58 participants with chronic anomia due to aphasia.
  • Focuses on improving word retrieval and generalization to untrained nouns.
  • Documents significant improvements in naming accuracy for both treatments.
Mahak Torabi
19 pages
Language:English
Type:Research Paper
History
Mahak Torabi
19 pages
Language:English
Type:Research Paper
History
271
/ 19
JSLHR
Research Article
Phonomotor Versus Semantic Feature
Analysis Treatment for Anomia
in 58 Persons With Aphasia:
A Randomized Controlled Trial
Diane L. Kendall,
a,b,c
Megan Oelke Moldestad,
a,b
Wesley Allen,
a,b,d
Janaki Torrence,
b
and Stephen E. Nadeau
e,f
Purpose: Theultimategoalofanomiatreatmentshould
be to achieve gains in exemplars trained in the therapy
session, as well as generalization to untrained exemplars
and contexts. The purpose of this study was to test the
efficacy of phonomotor treatment, a treatment focusing on
enhancement of phonological sequence knowledge, against
semantic feature analysis (SFA), a lexical-semantic therapy
that focuses on enhancement of semantic knowledge and
is well known and commonly used to treat anomia in aphasia.
Method: In a between-groups randomized controlled trial,
58 persons with aphasia characterized by anomia and
phonological dysfunction were randomized to receive
56–60 hr of intensively delivered treatment over 6 weeks
with testing pretreatment, posttreatment, and 3 months
posttreatment termination.
Results: There was no significant between-groups
difference on the primary outcome measure (untrained
nouns phonologically and semantically unrelated to each
treatment) at 3 months posttreatment. Significant within-
group immediately posttreatment acquisition effects for
confrontation naming and response latency were observed
for both groups. Treatment-specific generalization effects
for confrontation naming were observed for both groups
immediately and 3 months posttreatment; a significant
decrease in response latency was observed at both time
points for the SFA group only. Finally, significant within-group
differences on the Comprehensive Aphasia Test–Disability
Questionnaire (Swinburn, Porter, & Howard, 2004) were
observed both immediately and 3 months posttreatment for
the SFA group, and significant within-group differences
on the Functional Outcome Questionnaire (Glueckauf et al.,
2003) were found for both treatment groups 3 months
posttreatment.
Discussion: Our results are consistent with those of prior
studies that have shown that SFA treatment and phonomotor
treatment generalize to untrained words that share features
(semantic or phonological sequence, respectively) with the
training set. However, they show that there is no significant
generalization to untrained words that do not share semantic
features or phonological sequence features.
A
phasia, an acquired disorder of language typically
following stroke involving the left cerebral hemi-
sphere, negatively impacts daily life, the ability
to return to work, and social relationships. One common
and particularly disabling symptom of aphasia is anomia,
the inability to retrieve words, which results from under-
lying impairments of semantic, lexical-semantic, and/or
phonological processes. Rehabilitation of aphasia, mea-
sured in terms of learning of trained items, is effective
(Robey, 1994), and commonly delivered therapies, which
typically focus on semantic attributes of words, have been
shown to improve naming performance immediately
following treatment. Generalization to untrained words
and contexts with these therapies, however, is typically
limited to words that are semantically related to those in
a
Rehabilitation Research and Development Service, VA Puget Sound
DVA Medical Center, Seattle, WA
b
Department of Speech & Hearing Sciences, University of Washington,
Seattle
c
University of Pretoria, South Africa
d
Department of Speech and Hearing Sciences, Portland State
University, OR
e
Research Service, Malcom Randall VA Medical Center,
Gainesville, FL
f
Department of Neurology, University of Florida College of Medicine,
Gainesville
Correspondence to Diane L. Kendall: dkendall@uw.edu
Editor-in-Chief: Sean Redmond
Editor: Shannon Mauszycki
Received June 22, 2018
Revision received October 6, 2018
Accepted August 26, 2019
https://doi.org/10.1044/2019_JSLHR-L-18-0257
Disclosure: The authors have declared that no competing interests existed at the time
of publication.
Journal of Speech, Language, and Hearing Research
•
Vol. 62
•
4464–4482
•
December 2019
•
Copyright © 2019 American Speech-Language-Hearing Association4464
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the training corpus (Edmonds & Babb, 2011; Kiran &
Thompson, 2003a; Wiseburn & Mahoney, 2009). An alter-
native to commonly delivered aphasia therapies, called
phonomotor treatment (PMT ), focuses o n improving
knowledge of individual phonemes and phoneme sequences
(i.e., phonological sequence knowledge). Through a series
of Phase I and Phase II trials, we have shown that inten-
sively delivered PMT not only improves confrontation
naming performance on trained words but, as predicted by
the theory motivating it, also achieves generalization and
maintenance to naming of untrained words, some aspects
of discourse production, and indicators of quality of life
(Kendall, Oelke, Brookshire, & Nadeau, 2015; Kendall
et al., 2008). Furthermore, PMT has been shown to alter
the linguistic network, as evidenced by a decrease in omis-
sion errors immediately posttreatment and 3 months later
(Minkina et al., 2015), and to improve oral reading of real
words and nonwords following treatment (Brookshire,
Conway, Hunting Pompon, Oelke, & Kendall, 2014). The
long-term goal of this line of research is to establish an
effective, viable, and evidence-based treatment program for
word retrieval deficits in aphasia.
The purpose of this study is to test the efficacy of
PMT, a treatment focusing on enhancement of phonologi-
cal sequence knowledge, against semantic feature analysis
(SFA), a lexical-semantic therapy that focuses on enhance-
ment of semantic knowledge and is well known and
commonly used to treat anomia in aphasia. Because the
ultimate goal of aphasia treatment should be to improv e
daily verbal communication, hence performance with
untrained exemplars, our primary outcome measure assesses
generalization. Both the treatments used in this study have
an intrinsic capacity for generalization to untrained exem-
plars that share features (Nadeau, 2015).
PMT is motivated by a connectionist model of pho-
nology (Nadeau, 2001, 2012, 2015) that has been exten-
sively detailed (Kendall & Nadeau, 2016; Kendall et al.,
2015, 2008) and will be only briefly summarized here. The
version of PMT used in this study and the secondary out-
come measure employed (generalization to untrained but
phonologically related words) are precisely the same as
those used in Kendall et al. (2015). The theoretical founda-
tion for PMT is as follows: Through the systematic train-
ing o f p honemes (sounds) a nd phoneme sequen ces, t he
neural connectivity supporting phoneme sequence knowl-
edge will be enhanced. For example, if one trains the pho-
neme sequence corresponding to “must” to criterion, the
ability to say bust, dust, gust, just, lust, and trust will be
enhanced because all these words share the rhyme features
of “must.” Because phoneme articulatory sequences
correspond to the word forms of concept representations
founded on semantic knowledge, through bidirectional
spread of activation between cortical substrates for seman-
tic and phonological sequence knowledge, generalization
from treated phonemes can be expected to improve naming
of untrained words and discourse production, both imme-
diately after treatment and continued beyond treatment
termination. As in normal language development in children,
when adults with anomia due to aphasia are trained in the
phonemic sequence building blocks of word representa-
tions, they should be able to continue to build vocabulary
after termination of treatment.
The lexical-semantic–based treatment to which PMT
will be compared in this study is SFA. SFA is a treatment
approach that aims to improve lexical retrieval through
systematic stimulation of semantic features by elicitation of
prompts about individual nouns (e.g., group, description,
function, context, and personal associations). The hypothesis
motivating this treatment is that strengthening connectivity
in association cortices encoding semantic knowledge will
increase the likelihood that trained and semantically related
untrained words can be retrieved. Thus, training the inter-
feature connectivity in semantic cortices underlying the
concept of dog will enhance the ability to form distributed
concept representations of wolves, coyotes, and foxes because
these creatures share so many attributes with dogs. A recent
evidence-based systematic review of the effectiveness of
SFA (Maddy, Capilouto, & McComas, 2014) showed that
SFA is an effective intervention for improving confrontation
naming of items trained in therapy for individuals with
aphasia (medium-to-large treatment effect), though limited
generalization to untrained items and connected speech
were reported in many of the included studies. The limited
generalization of SFA reflects the challenge of treating a
sufficient number of semantic domains (e.g., tools and ani-
mals) and treating an adequate number of items in each
domain to achieve broad generalization and translation to
daily verbal communicatio n. Enhancing neural connectiv-
ity supporting one semantic category does not generalize
to a category that does not share semantic attributes.
Naming therapy (simply having participants prac-
tice naming objects) theoretically should not generalize
because, with the exception of onomatopoeic words and
derivational forms, there is no relationship between word
meaning and word sound. Because semantic knowledge
and phonological sequence knowledge share no common
features, there is essentially no opportunity for the semantic–
phonological sequence knowledge network to acquire
implicit knowledge of regularities in the relationship
between word meaning and word sound through the course
of language acquisition (in dramatic contrast to the domains
of semantic knowledge and phonological sequence knowl-
edge). In short, if you have learned to name 40 objects, this
knowledge provides no help in naming a heretofore unseen
41st object. Empirical studies bear this out (Wisenburn &
Mahoney, 2009).
Intrinsic generalization, the mechanism we sought to
engage in this study, is based on the extent to which un-
trained exemplars of any type share features with trained
exemplars. With PMT, there is a potential for generaliza-
tion to untrained exemplars that share phonological
sequence elements with trained sequences. With SFA, there
is the potential for generalization to untrained exemplars
that share semantic features with trained entities. To fully
understand intrinsic generalization, one needs to understand
both the structure of the knowledge domain in question
Kendall et al.: Phonomotor Versus Semantic Feature Analysis: RCT 4465
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and what qualifies as a shared feature. In the phonological
domain, words like “must,”“trust,” and “bust” share the
same sequence domain by virtue of their shared rhyme
segment. However, it remains to be determined whether
some generalization might occur between sequences shar-
ing smaller elements, for example, the final consonant
cluster “st, ” both within the “ust” domainandinother
sequence domains (e.g., blast, best, fist, most, and first).
Within the domain of semantics, the sharing of features
between dogs and wolves is extensive and obvious, but is
there enough sharing between dogs and more atypical
animal exemplars such as platypuses, sharks, or squids to
achieve generalization effects?
At the time that this study was initiated, the phono-
logical sequence landscape was poorly understood, and the
extent to which generalization could occur was unknown.
We had only our own published studies, and the modest
effect sizes (ESs) we had observed coul d have been related
to many treatment parameters other than generalization
constrained by sequence domain and segment length. On
the other hand, there exists considerable evidence that ca-
pacity for generalization with SFA is limited, as theoretically
predicted, to untrained exemplars that share many semantic
features (e.g., body parts, food, and clothing), but the role
of feature distance, though less well understood, is likely to
be important, for example, the relationship between finger
and thumb is likely to be stronger than that between finger
and lung. Thus, f or both phonological sequence knowl-
edge and semantic knowledge, much remains to be learned
about the structure of the knowledge domains and what
qualifies as a shared feature for treatment purposes.
All participants in this study had to have both anomia
and phonological dysfunction: anomia, because improve-
ment of ability to produce major lexical items on confron-
tation naming was the goal of the study, and phonological
impairment, because PMT seeks to improve anomia by
rehabilitating lost phonological sequence knowledge. The
combination of anomia and phonological impairment is
by far the most common pattern in poststroke aphasia
because aphasia due to stroke is most often caused by middle
cerebral artery occlusion or putamenal hemorrhage. With
middle cerebral artery occlusion, ischemia is maximal in
the insula and in the perisylvian cortex, which is the sub-
strate for phonological sequence knowledge (Nadeau,
2001; Nadeau & Crosson, 1997). With putamenal hemor-
rhage, the perisylvian cortex and its juxtacortical white
matter are damag ed by co mpressive and h ematotoxic
mechanisms. All participants in this study have lesions in
the perisylvian region and are thus representative of the
general population of people with stroke-related aphasia.
The primary aim of this study is to determine if PMT
or SFA is more effective for improving word retrieval defi-
cits in individuals with aphasia. The following research
questions were asked:
Primary Question:
1. Is there a significant “between-groups” difference
in confrontation naming accuracy and response
latency, measured 3 months posttreatment, for
nouns that are “untrained as well as semantically
and phonologically unrelated to trained stimuli”?
Secondary Questions:
2. Acquisition: Is there a significant “within-group”
difference in confrontation naming accuracy and
response latency for “trained” nouns measured at
treatment completion?
3. Lexical-semantic generalization: Is there a significant
“within-group” difference, immediately posttreatment
termination and 3 months later, for confrontation
naming of nouns that are both “untrained as well as
semantically and phonologically related to trained
stimuli”?
4. Ecological validity: Do these treatments achieve a
significan t “between-groups” or “within-gr oup” differ-
ence in two measures of ecological validity imme-
diately and 3 months posttreatment?
Method
Study Design
The design of this study was a between-groups ran-
domized controlled trial with repeated testing. Following
randomization, all participants received testing 1 week
prior to treatment (A1), immediately following treatment
(A2), and again 3 months following the termination of
treatment (A3). Standardized assessments and outcome
measures were administered at all assessment periods (A1,
A2, and A3). Individual, impairment-based speech therapy
outside the study was not permitted while participants were
enrolled, but participation in group communication therapy
was allowed.
Participants
Participants were recruited through the Veterans Af-
fairs Puget Sound Health Care System (Seattle and Ameri-
can Lake) and the University of Washington/Portland
State University Northwest Aphasia Registry and Reposi-
tory, as well as area speech-language pathology clinics.
Ninety-six participants were screened, and 21 failed the
screen due to prior neurological events. Fifteen individuals
passed the screen and were deemed eligible but declined to
participate. A total of 60 participants were recruited and
enrolled, and 58 completed the treatment protocol. One
enrolled individual completed the treatm ent pr otocol and
A1–A 2 testing but did not participate in A3 testing for per-
sonal reasons. Two individuals were withdrawn from the
study after consent (one following discovery of premorbid
head trauma and the other following a persona l emer-
gency). This study was conducted under the auspices of
the University of Washington Institutional Review Board,
and all participants personally provided informed consent
to take part in the study.
4466 Journal of Speech, Language, and Hearing Research
•
Vol. 62
•
4464–4482
•
December 2019
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You May Also Like

FAQs

What is phonomotor treatment and how does it work?
Phonomotor treatment (PMT) focuses on enhancing phonological sequence knowledge to improve word retrieval in individuals with aphasia. It involves systematic training of phonemes and phoneme sequences through multimodal tasks. Participants learn to produce sounds in isolation and then in combinations, progressing from simple to complex sequences. The aim is to strengthen the neural connections associated with phonological processing, ultimately aiding in the retrieval of both trained and untrained words.
What is semantic feature analysis and its purpose?
Semantic feature analysis (SFA) is a therapeutic approach that enhances word retrieval by stimulating semantic networks. This method involves prompting participants to generate features related to a target noun, such as its category, description, function, context, and personal associations. By strengthening the connections within semantic memory, SFA aims to improve the ability to name trained items and facilitate generalization to untrained words.
What were the main findings of the study comparing PMT and SFA?
The study found that both phonomotor treatment and semantic feature analysis led to significant improvements in naming accuracy for trained words. However, there were no significant differences between the two treatments in terms of generalization to untrained nouns. Both methods demonstrated effectiveness in enhancing word retrieval, but the lack of substantial differences suggests that either approach could be beneficial for individuals with aphasia.
How does this research contribute to aphasia treatment?
This research provides valuable insights into the effectiveness of two prominent treatment methods for anomia in aphasia. By comparing phonomotor treatment and semantic feature analysis, the study highlights the potential for both approaches to improve word retrieval. The findings can guide speech-language pathologists in selecting appropriate interventions tailored to individual patient needs, ultimately enhancing rehabilitation outcomes for those affected by aphasia.

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